The present disclosure relates to a rotation angle detection device for detecting a rotation angle of a rotation member.
A rotation angle detection device of a rotation member is taught, for example, by JP 2012-516434 A. As shown in FIG. 19, the rotation angle detection device A10 includes a magnetic detection member A12 for detecting a rotation angle of the rotation member, a holding member A13 holding the magnetic detection member A12, and a plurality of wiring members A14 for detection attached to the holding member A13 and connected to the magnetic detection member A12. With reference to mutually orthogonal three axes X, Y and Z (X-axis directions, Y-axis directions, and Z-axis directions) shown in FIG. 19, the magnetic detection member A12 has a plate-shaped main body portion A16 of which the thickness directions corresponds to the Z-axis directions, a plurality of lead terminals A18 projected in a negative direction of the Y-axis directions and positioned parallel to each other.
The plurality of lead terminals A18 of the magnetic detection member A12 are respectively bent into an L-shape such that distal end portions thereof can be extended in a positive direction along the Z-axis direction. The wiring members A14 for detection are positioned in parallel to each other. Further, the wiring members A14 for detection respectively have lead terminal connecting portions A14a extending in the same directions of the distal end portions of the lead terminals A18. The main body portion A16 of the magnetic detection member A12 is disposed on the holding member A13. The holding member A13 has a first positioning portion A21, second positioning portions A22, third positioning portions A23, and fourth positioning portions A24 for positioning the main body portion A16 of the magnetic detection member A12 thereon.
The main body portion A16 is positioned in a positive direction along the Y-axis direction by the first positioning portion A21. The main body portion A16 is positioned in a positive direction along the X-axis direction by the second positioning portion A22. The main body portion A16 is positioned in a negative direction along the X-axis direction by the third positioning portion A23. Further, the main body portion A16 is positioned in the positive direction along the Z-axis direction by crimping or swaging of the fourth positioning portion A24. The distal end portions of the lead terminals A18 of the magnetic detection member A12 are laid on the lead terminal connecting portions A14a in the Y-axis direction and bonded to each other by a welding method.
In the rotation angle detection device A10 thus constructed, the magnetic detection member A12 can be restricted from moving in the positive direction along the Y-axis direction (longitudinal direction) on the holding member A13 by means of the first positioning portion A21 and the fourth positioning portion A24. In addition, the magnetic detection member A12 can be restricted from moving in the negative direction along the Y-axis direction on the holding member A13 by means of welded portions formed between the lead terminals A18 and the lead terminal connecting portions A14a. That is, the magnetic detection member A12 can be constrained along the Y-axis directions. Thus, when the holding member A13 is elongated and contracted in the longitudinal direction by heat, the lead terminals A18 of the magnetic detection member A12 can be elongated and contracted, so that the lead terminals A18 can be stressed repeatedly. In particular, because the lead terminals A18 are bent into the L-shape to form bent portions thereon, the lead terminals A18 can be broken by stress concentrations in the bent portions.
Thus, there is a need in the art for an improved rotation angle detection device.